linux/include/linux/sched.h
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   1#ifndef _LINUX_SCHED_H
   2#define _LINUX_SCHED_H
   3
   4/*
   5 * cloning flags:
   6 */
   7#define CSIGNAL         0x000000ff      /* signal mask to be sent at exit */
   8#define CLONE_VM        0x00000100      /* set if VM shared between processes */
   9#define CLONE_FS        0x00000200      /* set if fs info shared between processes */
  10#define CLONE_FILES     0x00000400      /* set if open files shared between processes */
  11#define CLONE_SIGHAND   0x00000800      /* set if signal handlers and blocked signals shared */
  12#define CLONE_PTRACE    0x00002000      /* set if we want to let tracing continue on the child too */
  13#define CLONE_VFORK     0x00004000      /* set if the parent wants the child to wake it up on mm_release */
  14#define CLONE_PARENT    0x00008000      /* set if we want to have the same parent as the cloner */
  15#define CLONE_THREAD    0x00010000      /* Same thread group? */
  16#define CLONE_NEWNS     0x00020000      /* New namespace group? */
  17#define CLONE_SYSVSEM   0x00040000      /* share system V SEM_UNDO semantics */
  18#define CLONE_SETTLS    0x00080000      /* create a new TLS for the child */
  19#define CLONE_PARENT_SETTID     0x00100000      /* set the TID in the parent */
  20#define CLONE_CHILD_CLEARTID    0x00200000      /* clear the TID in the child */
  21#define CLONE_DETACHED          0x00400000      /* Unused, ignored */
  22#define CLONE_UNTRACED          0x00800000      /* set if the tracing process can't force CLONE_PTRACE on this clone */
  23#define CLONE_CHILD_SETTID      0x01000000      /* set the TID in the child */
  24#define CLONE_STOPPED           0x02000000      /* Start in stopped state */
  25#define CLONE_NEWUTS            0x04000000      /* New utsname group? */
  26#define CLONE_NEWIPC            0x08000000      /* New ipcs */
  27#define CLONE_NEWUSER           0x10000000      /* New user namespace */
  28#define CLONE_NEWPID            0x20000000      /* New pid namespace */
  29#define CLONE_NEWNET            0x40000000      /* New network namespace */
  30#define CLONE_IO                0x80000000      /* Clone io context */
  31
  32/*
  33 * Scheduling policies
  34 */
  35#define SCHED_NORMAL            0
  36#define SCHED_FIFO              1
  37#define SCHED_RR                2
  38#define SCHED_BATCH             3
  39/* SCHED_ISO: reserved but not implemented yet */
  40#define SCHED_IDLE              5
  41
  42#ifdef __KERNEL__
  43
  44struct sched_param {
  45        int sched_priority;
  46};
  47
  48#include <asm/param.h>  /* for HZ */
  49
  50#include <linux/capability.h>
  51#include <linux/threads.h>
  52#include <linux/kernel.h>
  53#include <linux/types.h>
  54#include <linux/timex.h>
  55#include <linux/jiffies.h>
  56#include <linux/rbtree.h>
  57#include <linux/thread_info.h>
  58#include <linux/cpumask.h>
  59#include <linux/errno.h>
  60#include <linux/nodemask.h>
  61#include <linux/mm_types.h>
  62
  63#include <asm/system.h>
  64#include <asm/page.h>
  65#include <asm/ptrace.h>
  66#include <asm/cputime.h>
  67
  68#include <linux/smp.h>
  69#include <linux/sem.h>
  70#include <linux/signal.h>
  71#include <linux/path.h>
  72#include <linux/compiler.h>
  73#include <linux/completion.h>
  74#include <linux/pid.h>
  75#include <linux/percpu.h>
  76#include <linux/topology.h>
  77#include <linux/proportions.h>
  78#include <linux/seccomp.h>
  79#include <linux/rcupdate.h>
  80#include <linux/rculist.h>
  81#include <linux/rtmutex.h>
  82
  83#include <linux/time.h>
  84#include <linux/param.h>
  85#include <linux/resource.h>
  86#include <linux/timer.h>
  87#include <linux/hrtimer.h>
  88#include <linux/task_io_accounting.h>
  89#include <linux/kobject.h>
  90#include <linux/latencytop.h>
  91#include <linux/cred.h>
  92
  93#include <asm/processor.h>
  94
  95struct exec_domain;
  96struct futex_pi_state;
  97struct robust_list_head;
  98struct bio;
  99struct fs_struct;
 100struct bts_context;
 101struct perf_counter_context;
 102
 103/*
 104 * List of flags we want to share for kernel threads,
 105 * if only because they are not used by them anyway.
 106 */
 107#define CLONE_KERNEL    (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
 108
 109/*
 110 * These are the constant used to fake the fixed-point load-average
 111 * counting. Some notes:
 112 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
 113 *    a load-average precision of 10 bits integer + 11 bits fractional
 114 *  - if you want to count load-averages more often, you need more
 115 *    precision, or rounding will get you. With 2-second counting freq,
 116 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
 117 *    11 bit fractions.
 118 */
 119extern unsigned long avenrun[];         /* Load averages */
 120extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
 121
 122#define FSHIFT          11              /* nr of bits of precision */
 123#define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
 124#define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
 125#define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
 126#define EXP_5           2014            /* 1/exp(5sec/5min) */
 127#define EXP_15          2037            /* 1/exp(5sec/15min) */
 128
 129#define CALC_LOAD(load,exp,n) \
 130        load *= exp; \
 131        load += n*(FIXED_1-exp); \
 132        load >>= FSHIFT;
 133
 134extern unsigned long total_forks;
 135extern int nr_threads;
 136DECLARE_PER_CPU(unsigned long, process_counts);
 137extern int nr_processes(void);
 138extern unsigned long nr_running(void);
 139extern unsigned long nr_uninterruptible(void);
 140extern unsigned long nr_iowait(void);
 141extern void calc_global_load(void);
 142extern u64 cpu_nr_migrations(int cpu);
 143
 144extern unsigned long get_parent_ip(unsigned long addr);
 145
 146struct seq_file;
 147struct cfs_rq;
 148struct task_group;
 149#ifdef CONFIG_SCHED_DEBUG
 150extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
 151extern void proc_sched_set_task(struct task_struct *p);
 152extern void
 153print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
 154#else
 155static inline void
 156proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 157{
 158}
 159static inline void proc_sched_set_task(struct task_struct *p)
 160{
 161}
 162static inline void
 163print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 164{
 165}
 166#endif
 167
 168extern unsigned long long time_sync_thresh;
 169
 170/*
 171 * Task state bitmask. NOTE! These bits are also
 172 * encoded in fs/proc/array.c: get_task_state().
 173 *
 174 * We have two separate sets of flags: task->state
 175 * is about runnability, while task->exit_state are
 176 * about the task exiting. Confusing, but this way
 177 * modifying one set can't modify the other one by
 178 * mistake.
 179 */
 180#define TASK_RUNNING            0
 181#define TASK_INTERRUPTIBLE      1
 182#define TASK_UNINTERRUPTIBLE    2
 183#define __TASK_STOPPED          4
 184#define __TASK_TRACED           8
 185/* in tsk->exit_state */
 186#define EXIT_ZOMBIE             16
 187#define EXIT_DEAD               32
 188/* in tsk->state again */
 189#define TASK_DEAD               64
 190#define TASK_WAKEKILL           128
 191
 192/* Convenience macros for the sake of set_task_state */
 193#define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 194#define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
 195#define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
 196
 197/* Convenience macros for the sake of wake_up */
 198#define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
 199#define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
 200
 201/* get_task_state() */
 202#define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
 203                                 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
 204                                 __TASK_TRACED)
 205
 206#define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
 207#define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
 208#define task_is_stopped_or_traced(task) \
 209                        ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 210#define task_contributes_to_load(task)  \
 211                                ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
 212                                 (task->flags & PF_FREEZING) == 0)
 213
 214#define __set_task_state(tsk, state_value)              \
 215        do { (tsk)->state = (state_value); } while (0)
 216#define set_task_state(tsk, state_value)                \
 217        set_mb((tsk)->state, (state_value))
 218
 219/*
 220 * set_current_state() includes a barrier so that the write of current->state
 221 * is correctly serialised wrt the caller's subsequent test of whether to
 222 * actually sleep:
 223 *
 224 *      set_current_state(TASK_UNINTERRUPTIBLE);
 225 *      if (do_i_need_to_sleep())
 226 *              schedule();
 227 *
 228 * If the caller does not need such serialisation then use __set_current_state()
 229 */
 230#define __set_current_state(state_value)                        \
 231        do { current->state = (state_value); } while (0)
 232#define set_current_state(state_value)          \
 233        set_mb(current->state, (state_value))
 234
 235/* Task command name length */
 236#define TASK_COMM_LEN 16
 237
 238#include <linux/spinlock.h>
 239
 240/*
 241 * This serializes "schedule()" and also protects
 242 * the run-queue from deletions/modifications (but
 243 * _adding_ to the beginning of the run-queue has
 244 * a separate lock).
 245 */
 246extern rwlock_t tasklist_lock;
 247extern spinlock_t mmlist_lock;
 248
 249struct task_struct;
 250
 251extern void sched_init(void);
 252extern void sched_init_smp(void);
 253extern asmlinkage void schedule_tail(struct task_struct *prev);
 254extern void init_idle(struct task_struct *idle, int cpu);
 255extern void init_idle_bootup_task(struct task_struct *idle);
 256
 257extern int runqueue_is_locked(void);
 258extern void task_rq_unlock_wait(struct task_struct *p);
 259
 260extern cpumask_var_t nohz_cpu_mask;
 261#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
 262extern int select_nohz_load_balancer(int cpu);
 263extern int get_nohz_load_balancer(void);
 264#else
 265static inline int select_nohz_load_balancer(int cpu)
 266{
 267        return 0;
 268}
 269#endif
 270
 271/*
 272 * Only dump TASK_* tasks. (0 for all tasks)
 273 */
 274extern void show_state_filter(unsigned long state_filter);
 275
 276static inline void show_state(void)
 277{
 278        show_state_filter(0);
 279}
 280
 281extern void show_regs(struct pt_regs *);
 282
 283/*
 284 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
 285 * task), SP is the stack pointer of the first frame that should be shown in the back
 286 * trace (or NULL if the entire call-chain of the task should be shown).
 287 */
 288extern void show_stack(struct task_struct *task, unsigned long *sp);
 289
 290void io_schedule(void);
 291long io_schedule_timeout(long timeout);
 292
 293extern void cpu_init (void);
 294extern void trap_init(void);
 295extern void update_process_times(int user);
 296extern void scheduler_tick(void);
 297
 298extern void sched_show_task(struct task_struct *p);
 299
 300#ifdef CONFIG_DETECT_SOFTLOCKUP
 301extern void softlockup_tick(void);
 302extern void touch_softlockup_watchdog(void);
 303extern void touch_all_softlockup_watchdogs(void);
 304extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
 305                                    struct file *filp, void __user *buffer,
 306                                    size_t *lenp, loff_t *ppos);
 307extern unsigned int  softlockup_panic;
 308extern int softlockup_thresh;
 309#else
 310static inline void softlockup_tick(void)
 311{
 312}
 313static inline void touch_softlockup_watchdog(void)
 314{
 315}
 316static inline void touch_all_softlockup_watchdogs(void)
 317{
 318}
 319#endif
 320
 321#ifdef CONFIG_DETECT_HUNG_TASK
 322extern unsigned int  sysctl_hung_task_panic;
 323extern unsigned long sysctl_hung_task_check_count;
 324extern unsigned long sysctl_hung_task_timeout_secs;
 325extern unsigned long sysctl_hung_task_warnings;
 326extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
 327                                         struct file *filp, void __user *buffer,
 328                                         size_t *lenp, loff_t *ppos);
 329#endif
 330
 331/* Attach to any functions which should be ignored in wchan output. */
 332#define __sched         __attribute__((__section__(".sched.text")))
 333
 334/* Linker adds these: start and end of __sched functions */
 335extern char __sched_text_start[], __sched_text_end[];
 336
 337/* Is this address in the __sched functions? */
 338extern int in_sched_functions(unsigned long addr);
 339
 340#define MAX_SCHEDULE_TIMEOUT    LONG_MAX
 341extern signed long schedule_timeout(signed long timeout);
 342extern signed long schedule_timeout_interruptible(signed long timeout);
 343extern signed long schedule_timeout_killable(signed long timeout);
 344extern signed long schedule_timeout_uninterruptible(signed long timeout);
 345asmlinkage void __schedule(void);
 346asmlinkage void schedule(void);
 347extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
 348
 349struct nsproxy;
 350struct user_namespace;
 351
 352/*
 353 * Default maximum number of active map areas, this limits the number of vmas
 354 * per mm struct. Users can overwrite this number by sysctl but there is a
 355 * problem.
 356 *
 357 * When a program's coredump is generated as ELF format, a section is created
 358 * per a vma. In ELF, the number of sections is represented in unsigned short.
 359 * This means the number of sections should be smaller than 65535 at coredump.
 360 * Because the kernel adds some informative sections to a image of program at
 361 * generating coredump, we need some margin. The number of extra sections is
 362 * 1-3 now and depends on arch. We use "5" as safe margin, here.
 363 */
 364#define MAPCOUNT_ELF_CORE_MARGIN        (5)
 365#define DEFAULT_MAX_MAP_COUNT   (USHORT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
 366
 367extern int sysctl_max_map_count;
 368
 369#include <linux/aio.h>
 370
 371extern unsigned long
 372arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
 373                       unsigned long, unsigned long);
 374extern unsigned long
 375arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 376                          unsigned long len, unsigned long pgoff,
 377                          unsigned long flags);
 378extern void arch_unmap_area(struct mm_struct *, unsigned long);
 379extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
 380
 381#if USE_SPLIT_PTLOCKS
 382/*
 383 * The mm counters are not protected by its page_table_lock,
 384 * so must be incremented atomically.
 385 */
 386#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
 387#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
 388#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
 389#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
 390#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
 391
 392#else  /* !USE_SPLIT_PTLOCKS */
 393/*
 394 * The mm counters are protected by its page_table_lock,
 395 * so can be incremented directly.
 396 */
 397#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
 398#define get_mm_counter(mm, member) ((mm)->_##member)
 399#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
 400#define inc_mm_counter(mm, member) (mm)->_##member++
 401#define dec_mm_counter(mm, member) (mm)->_##member--
 402
 403#endif /* !USE_SPLIT_PTLOCKS */
 404
 405#define get_mm_rss(mm)                                  \
 406        (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
 407#define update_hiwater_rss(mm)  do {                    \
 408        unsigned long _rss = get_mm_rss(mm);            \
 409        if ((mm)->hiwater_rss < _rss)                   \
 410                (mm)->hiwater_rss = _rss;               \
 411} while (0)
 412#define update_hiwater_vm(mm)   do {                    \
 413        if ((mm)->hiwater_vm < (mm)->total_vm)          \
 414                (mm)->hiwater_vm = (mm)->total_vm;      \
 415} while (0)
 416
 417static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
 418{
 419        return max(mm->hiwater_rss, get_mm_rss(mm));
 420}
 421
 422static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
 423{
 424        return max(mm->hiwater_vm, mm->total_vm);
 425}
 426
 427extern void set_dumpable(struct mm_struct *mm, int value);
 428extern int get_dumpable(struct mm_struct *mm);
 429
 430/* mm flags */
 431/* dumpable bits */
 432#define MMF_DUMPABLE      0  /* core dump is permitted */
 433#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
 434#define MMF_DUMPABLE_BITS 2
 435
 436/* coredump filter bits */
 437#define MMF_DUMP_ANON_PRIVATE   2
 438#define MMF_DUMP_ANON_SHARED    3
 439#define MMF_DUMP_MAPPED_PRIVATE 4
 440#define MMF_DUMP_MAPPED_SHARED  5
 441#define MMF_DUMP_ELF_HEADERS    6
 442#define MMF_DUMP_HUGETLB_PRIVATE 7
 443#define MMF_DUMP_HUGETLB_SHARED  8
 444#define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
 445#define MMF_DUMP_FILTER_BITS    7
 446#define MMF_DUMP_FILTER_MASK \
 447        (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
 448#define MMF_DUMP_FILTER_DEFAULT \
 449        ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
 450         (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
 451
 452#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
 453# define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
 454#else
 455# define MMF_DUMP_MASK_DEFAULT_ELF      0
 456#endif
 457
 458struct sighand_struct {
 459        atomic_t                count;
 460        struct k_sigaction      action[_NSIG];
 461        spinlock_t              siglock;
 462        wait_queue_head_t       signalfd_wqh;
 463};
 464
 465struct pacct_struct {
 466        int                     ac_flag;
 467        long                    ac_exitcode;
 468        unsigned long           ac_mem;
 469        cputime_t               ac_utime, ac_stime;
 470        unsigned long           ac_minflt, ac_majflt;
 471};
 472
 473/**
 474 * struct task_cputime - collected CPU time counts
 475 * @utime:              time spent in user mode, in &cputime_t units
 476 * @stime:              time spent in kernel mode, in &cputime_t units
 477 * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
 478 *
 479 * This structure groups together three kinds of CPU time that are
 480 * tracked for threads and thread groups.  Most things considering
 481 * CPU time want to group these counts together and treat all three
 482 * of them in parallel.
 483 */
 484struct task_cputime {
 485        cputime_t utime;
 486        cputime_t stime;
 487        unsigned long long sum_exec_runtime;
 488};
 489/* Alternate field names when used to cache expirations. */
 490#define prof_exp        stime
 491#define virt_exp        utime
 492#define sched_exp       sum_exec_runtime
 493
 494#define INIT_CPUTIME    \
 495        (struct task_cputime) {                                 \
 496                .utime = cputime_zero,                          \
 497                .stime = cputime_zero,                          \
 498                .sum_exec_runtime = 0,                          \
 499        }
 500
 501/*
 502 * Disable preemption until the scheduler is running.
 503 * Reset by start_kernel()->sched_init()->init_idle().
 504 *
 505 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
 506 * before the scheduler is active -- see should_resched().
 507 */
 508#define INIT_PREEMPT_COUNT      (1 + PREEMPT_ACTIVE)
 509
 510/**
 511 * struct thread_group_cputimer - thread group interval timer counts
 512 * @cputime:            thread group interval timers.
 513 * @running:            non-zero when there are timers running and
 514 *                      @cputime receives updates.
 515 * @lock:               lock for fields in this struct.
 516 *
 517 * This structure contains the version of task_cputime, above, that is
 518 * used for thread group CPU timer calculations.
 519 */
 520struct thread_group_cputimer {
 521        struct task_cputime cputime;
 522        int running;
 523        spinlock_t lock;
 524};
 525
 526/*
 527 * NOTE! "signal_struct" does not have it's own
 528 * locking, because a shared signal_struct always
 529 * implies a shared sighand_struct, so locking
 530 * sighand_struct is always a proper superset of
 531 * the locking of signal_struct.
 532 */
 533struct signal_struct {
 534        atomic_t                count;
 535        atomic_t                live;
 536
 537        wait_queue_head_t       wait_chldexit;  /* for wait4() */
 538
 539        /* current thread group signal load-balancing target: */
 540        struct task_struct      *curr_target;
 541
 542        /* shared signal handling: */
 543        struct sigpending       shared_pending;
 544
 545        /* thread group exit support */
 546        int                     group_exit_code;
 547        /* overloaded:
 548         * - notify group_exit_task when ->count is equal to notify_count
 549         * - everyone except group_exit_task is stopped during signal delivery
 550         *   of fatal signals, group_exit_task processes the signal.
 551         */
 552        int                     notify_count;
 553        struct task_struct      *group_exit_task;
 554
 555        /* thread group stop support, overloads group_exit_code too */
 556        int                     group_stop_count;
 557        unsigned int            flags; /* see SIGNAL_* flags below */
 558
 559        /* POSIX.1b Interval Timers */
 560        struct list_head posix_timers;
 561
 562        /* ITIMER_REAL timer for the process */
 563        struct hrtimer real_timer;
 564        struct pid *leader_pid;
 565        ktime_t it_real_incr;
 566
 567        /* ITIMER_PROF and ITIMER_VIRTUAL timers for the process */
 568        cputime_t it_prof_expires, it_virt_expires;
 569        cputime_t it_prof_incr, it_virt_incr;
 570
 571        /*
 572         * Thread group totals for process CPU timers.
 573         * See thread_group_cputimer(), et al, for details.
 574         */
 575        struct thread_group_cputimer cputimer;
 576
 577        /* Earliest-expiration cache. */
 578        struct task_cputime cputime_expires;
 579
 580        struct list_head cpu_timers[3];
 581
 582        struct pid *tty_old_pgrp;
 583
 584        /* boolean value for session group leader */
 585        int leader;
 586
 587        struct tty_struct *tty; /* NULL if no tty */
 588
 589        /*
 590         * Cumulative resource counters for dead threads in the group,
 591         * and for reaped dead child processes forked by this group.
 592         * Live threads maintain their own counters and add to these
 593         * in __exit_signal, except for the group leader.
 594         */
 595        cputime_t utime, stime, cutime, cstime;
 596        cputime_t gtime;
 597        cputime_t cgtime;
 598        unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 599        unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 600        unsigned long inblock, oublock, cinblock, coublock;
 601        struct task_io_accounting ioac;
 602
 603        /*
 604         * Cumulative ns of schedule CPU time fo dead threads in the
 605         * group, not including a zombie group leader, (This only differs
 606         * from jiffies_to_ns(utime + stime) if sched_clock uses something
 607         * other than jiffies.)
 608         */
 609        unsigned long long sum_sched_runtime;
 610
 611        /*
 612         * We don't bother to synchronize most readers of this at all,
 613         * because there is no reader checking a limit that actually needs
 614         * to get both rlim_cur and rlim_max atomically, and either one
 615         * alone is a single word that can safely be read normally.
 616         * getrlimit/setrlimit use task_lock(current->group_leader) to
 617         * protect this instead of the siglock, because they really
 618         * have no need to disable irqs.
 619         */
 620        struct rlimit rlim[RLIM_NLIMITS];
 621
 622#ifdef CONFIG_BSD_PROCESS_ACCT
 623        struct pacct_struct pacct;      /* per-process accounting information */
 624#endif
 625#ifdef CONFIG_TASKSTATS
 626        struct taskstats *stats;
 627#endif
 628#ifdef CONFIG_AUDIT
 629        unsigned audit_tty;
 630        struct tty_audit_buf *tty_audit_buf;
 631#endif
 632};
 633
 634/* Context switch must be unlocked if interrupts are to be enabled */
 635#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
 636# define __ARCH_WANT_UNLOCKED_CTXSW
 637#endif
 638
 639/*
 640 * Bits in flags field of signal_struct.
 641 */
 642#define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
 643#define SIGNAL_STOP_DEQUEUED    0x00000002 /* stop signal dequeued */
 644#define SIGNAL_STOP_CONTINUED   0x00000004 /* SIGCONT since WCONTINUED reap */
 645#define SIGNAL_GROUP_EXIT       0x00000008 /* group exit in progress */
 646/*
 647 * Pending notifications to parent.
 648 */
 649#define SIGNAL_CLD_STOPPED      0x00000010
 650#define SIGNAL_CLD_CONTINUED    0x00000020
 651#define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
 652
 653#define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
 654
 655/* If true, all threads except ->group_exit_task have pending SIGKILL */
 656static inline int signal_group_exit(const struct signal_struct *sig)
 657{
 658        return  (sig->flags & SIGNAL_GROUP_EXIT) ||
 659                (sig->group_exit_task != NULL);
 660}
 661
 662/*
 663 * Some day this will be a full-fledged user tracking system..
 664 */
 665struct user_struct {
 666        atomic_t __count;       /* reference count */
 667        atomic_t processes;     /* How many processes does this user have? */
 668        atomic_t files;         /* How many open files does this user have? */
 669        atomic_t sigpending;    /* How many pending signals does this user have? */
 670#ifdef CONFIG_INOTIFY_USER
 671        atomic_t inotify_watches; /* How many inotify watches does this user have? */
 672        atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
 673#endif
 674#ifdef CONFIG_EPOLL
 675        atomic_t epoll_watches; /* The number of file descriptors currently watched */
 676#endif
 677#ifdef CONFIG_POSIX_MQUEUE
 678        /* protected by mq_lock */
 679        unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
 680#endif
 681        unsigned long locked_shm; /* How many pages of mlocked shm ? */
 682
 683#ifdef CONFIG_KEYS
 684        struct key *uid_keyring;        /* UID specific keyring */
 685        struct key *session_keyring;    /* UID's default session keyring */
 686#endif
 687
 688        /* Hash table maintenance information */
 689        struct hlist_node uidhash_node;
 690        uid_t uid;
 691        struct user_namespace *user_ns;
 692
 693#ifdef CONFIG_USER_SCHED
 694        struct task_group *tg;
 695#ifdef CONFIG_SYSFS
 696        struct kobject kobj;
 697        struct delayed_work work;
 698#endif
 699#endif
 700
 701#ifdef CONFIG_PERF_COUNTERS
 702        atomic_long_t locked_vm;
 703#endif
 704};
 705
 706extern int uids_sysfs_init(void);
 707
 708extern struct user_struct *find_user(uid_t);
 709
 710extern struct user_struct root_user;
 711#define INIT_USER (&root_user)
 712
 713
 714struct backing_dev_info;
 715struct reclaim_state;
 716
 717#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
 718struct sched_info {
 719        /* cumulative counters */
 720        unsigned long pcount;         /* # of times run on this cpu */
 721        unsigned long long run_delay; /* time spent waiting on a runqueue */
 722
 723        /* timestamps */
 724        unsigned long long last_arrival,/* when we last ran on a cpu */
 725                           last_queued; /* when we were last queued to run */
 726#ifdef CONFIG_SCHEDSTATS
 727        /* BKL stats */
 728        unsigned int bkl_count;
 729#endif
 730};
 731#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
 732
 733#ifdef CONFIG_TASK_DELAY_ACCT
 734struct task_delay_info {
 735        spinlock_t      lock;
 736        unsigned int    flags;  /* Private per-task flags */
 737
 738        /* For each stat XXX, add following, aligned appropriately
 739         *
 740         * struct timespec XXX_start, XXX_end;
 741         * u64 XXX_delay;
 742         * u32 XXX_count;
 743         *
 744         * Atomicity of updates to XXX_delay, XXX_count protected by
 745         * single lock above (split into XXX_lock if contention is an issue).
 746         */
 747
 748        /*
 749         * XXX_count is incremented on every XXX operation, the delay
 750         * associated with the operation is added to XXX_delay.
 751         * XXX_delay contains the accumulated delay time in nanoseconds.
 752         */
 753        struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
 754        u64 blkio_delay;        /* wait for sync block io completion */
 755        u64 swapin_delay;       /* wait for swapin block io completion */
 756        u32 blkio_count;        /* total count of the number of sync block */
 757                                /* io operations performed */
 758        u32 swapin_count;       /* total count of the number of swapin block */
 759                                /* io operations performed */
 760
 761        struct timespec freepages_start, freepages_end;
 762        u64 freepages_delay;    /* wait for memory reclaim */
 763        u32 freepages_count;    /* total count of memory reclaim */
 764};
 765#endif  /* CONFIG_TASK_DELAY_ACCT */
 766
 767static inline int sched_info_on(void)
 768{
 769#ifdef CONFIG_SCHEDSTATS
 770        return 1;
 771#elif defined(CONFIG_TASK_DELAY_ACCT)
 772        extern int delayacct_on;
 773        return delayacct_on;
 774#else
 775        return 0;
 776#endif
 777}
 778
 779enum cpu_idle_type {
 780        CPU_IDLE,
 781        CPU_NOT_IDLE,
 782        CPU_NEWLY_IDLE,
 783        CPU_MAX_IDLE_TYPES
 784};
 785
 786/*
 787 * sched-domains (multiprocessor balancing) declarations:
 788 */
 789
 790/*
 791 * Increase resolution of nice-level calculations:
 792 */
 793#define SCHED_LOAD_SHIFT        10
 794#define SCHED_LOAD_SCALE        (1L << SCHED_LOAD_SHIFT)
 795
 796#define SCHED_LOAD_SCALE_FUZZ   SCHED_LOAD_SCALE
 797
 798#ifdef CONFIG_SMP
 799#define SD_LOAD_BALANCE         1       /* Do load balancing on this domain. */
 800#define SD_BALANCE_NEWIDLE      2       /* Balance when about to become idle */
 801#define SD_BALANCE_EXEC         4       /* Balance on exec */
 802#define SD_BALANCE_FORK         8       /* Balance on fork, clone */
 803#define SD_WAKE_IDLE            16      /* Wake to idle CPU on task wakeup */
 804#define SD_WAKE_AFFINE          32      /* Wake task to waking CPU */
 805#define SD_WAKE_BALANCE         64      /* Perform balancing at task wakeup */
 806#define SD_SHARE_CPUPOWER       128     /* Domain members share cpu power */
 807#define SD_POWERSAVINGS_BALANCE 256     /* Balance for power savings */
 808#define SD_SHARE_PKG_RESOURCES  512     /* Domain members share cpu pkg resources */
 809#define SD_SERIALIZE            1024    /* Only a single load balancing instance */
 810#define SD_WAKE_IDLE_FAR        2048    /* Gain latency sacrificing cache hit */
 811
 812enum powersavings_balance_level {
 813        POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
 814        POWERSAVINGS_BALANCE_BASIC,     /* Fill one thread/core/package
 815                                         * first for long running threads
 816                                         */
 817        POWERSAVINGS_BALANCE_WAKEUP,    /* Also bias task wakeups to semi-idle
 818                                         * cpu package for power savings
 819                                         */
 820        MAX_POWERSAVINGS_BALANCE_LEVELS
 821};
 822
 823extern int sched_mc_power_savings, sched_smt_power_savings;
 824
 825static inline int sd_balance_for_mc_power(void)
 826{
 827        if (sched_smt_power_savings)
 828                return SD_POWERSAVINGS_BALANCE;
 829
 830        return 0;
 831}
 832
 833static inline int sd_balance_for_package_power(void)
 834{
 835        if (sched_mc_power_savings | sched_smt_power_savings)
 836                return SD_POWERSAVINGS_BALANCE;
 837
 838        return 0;
 839}
 840
 841/*
 842 * Optimise SD flags for power savings:
 843 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
 844 * Keep default SD flags if sched_{smt,mc}_power_saving=0
 845 */
 846
 847static inline int sd_power_saving_flags(void)
 848{
 849        if (sched_mc_power_savings | sched_smt_power_savings)
 850                return SD_BALANCE_NEWIDLE;
 851
 852        return 0;
 853}
 854
 855struct sched_group {
 856        struct sched_group *next;       /* Must be a circular list */
 857
 858        /*
 859         * CPU power of this group, SCHED_LOAD_SCALE being max power for a
 860         * single CPU. This is read only (except for setup, hotplug CPU).
 861         * Note : Never change cpu_power without recompute its reciprocal
 862         */
 863        unsigned int __cpu_power;
 864        /*
 865         * reciprocal value of cpu_power to avoid expensive divides
 866         * (see include/linux/reciprocal_div.h)
 867         */
 868        u32 reciprocal_cpu_power;
 869
 870        /*
 871         * The CPUs this group covers.
 872         *
 873         * NOTE: this field is variable length. (Allocated dynamically
 874         * by attaching extra space to the end of the structure,
 875         * depending on how many CPUs the kernel has booted up with)
 876         *
 877         * It is also be embedded into static data structures at build
 878         * time. (See 'struct static_sched_group' in kernel/sched.c)
 879         */
 880        unsigned long cpumask[0];
 881};
 882
 883static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
 884{
 885        return to_cpumask(sg->cpumask);
 886}
 887
 888enum sched_domain_level {
 889        SD_LV_NONE = 0,
 890        SD_LV_SIBLING,
 891        SD_LV_MC,
 892        SD_LV_CPU,
 893        SD_LV_NODE,
 894        SD_LV_ALLNODES,
 895        SD_LV_MAX
 896};
 897
 898struct sched_domain_attr {
 899        int relax_domain_level;
 900};
 901
 902#define SD_ATTR_INIT    (struct sched_domain_attr) {    \
 903        .relax_domain_level = -1,                       \
 904}
 905
 906struct sched_domain {
 907        /* These fields must be setup */
 908        struct sched_domain *parent;    /* top domain must be null terminated */
 909        struct sched_domain *child;     /* bottom domain must be null terminated */
 910        struct sched_group *groups;     /* the balancing groups of the domain */
 911        unsigned long min_interval;     /* Minimum balance interval ms */
 912        unsigned long max_interval;     /* Maximum balance interval ms */
 913        unsigned int busy_factor;       /* less balancing by factor if busy */
 914        unsigned int imbalance_pct;     /* No balance until over watermark */
 915        unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
 916        unsigned int busy_idx;
 917        unsigned int idle_idx;
 918        unsigned int newidle_idx;
 919        unsigned int wake_idx;
 920        unsigned int forkexec_idx;
 921        int flags;                      /* See SD_* */
 922        enum sched_domain_level level;
 923
 924        /* Runtime fields. */
 925        unsigned long last_balance;     /* init to jiffies. units in jiffies */
 926        unsigned int balance_interval;  /* initialise to 1. units in ms. */
 927        unsigned int nr_balance_failed; /* initialise to 0 */
 928
 929        u64 last_update;
 930
 931#ifdef CONFIG_SCHEDSTATS
 932        /* load_balance() stats */
 933        unsigned int lb_count[CPU_MAX_IDLE_TYPES];
 934        unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
 935        unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
 936        unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
 937        unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
 938        unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
 939        unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
 940        unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
 941
 942        /* Active load balancing */
 943        unsigned int alb_count;
 944        unsigned int alb_failed;
 945        unsigned int alb_pushed;
 946
 947        /* SD_BALANCE_EXEC stats */
 948        unsigned int sbe_count;
 949        unsigned int sbe_balanced;
 950        unsigned int sbe_pushed;
 951
 952        /* SD_BALANCE_FORK stats */
 953        unsigned int sbf_count;
 954        unsigned int sbf_balanced;
 955        unsigned int sbf_pushed;
 956
 957        /* try_to_wake_up() stats */
 958        unsigned int ttwu_wake_remote;
 959        unsigned int ttwu_move_affine;
 960        unsigned int ttwu_move_balance;
 961#endif
 962#ifdef CONFIG_SCHED_DEBUG
 963        char *name;
 964#endif
 965
 966        /*
 967         * Span of all CPUs in this domain.
 968         *
 969         * NOTE: this field is variable length. (Allocated dynamically
 970         * by attaching extra space to the end of the structure,
 971         * depending on how many CPUs the kernel has booted up with)
 972         *
 973         * It is also be embedded into static data structures at build
 974         * time. (See 'struct static_sched_domain' in kernel/sched.c)
 975         */
 976        unsigned long span[0];
 977};
 978
 979static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
 980{
 981        return to_cpumask(sd->span);
 982}
 983
 984extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
 985                                    struct sched_domain_attr *dattr_new);
 986
 987/* Test a flag in parent sched domain */
 988static inline int test_sd_parent(struct sched_domain *sd, int flag)
 989{
 990        if (sd->parent && (sd->parent->flags & flag))
 991                return 1;
 992
 993        return 0;
 994}
 995
 996#else /* CONFIG_SMP */
 997
 998struct sched_domain_attr;
 999
1000static inline void
1001partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
1002                        struct sched_domain_attr *dattr_new)
1003{
1004}
1005#endif  /* !CONFIG_SMP */
1006
1007struct io_context;                      /* See blkdev.h */
1008
1009
1010#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1011extern void prefetch_stack(struct task_struct *t);
1012#else
1013static inline void prefetch_stack(struct task_struct *t) { }
1014#endif
1015
1016struct audit_context;           /* See audit.c */
1017struct mempolicy;
1018struct pipe_inode_info;
1019struct uts_namespace;
1020
1021struct rq;
1022struct sched_domain;
1023
1024struct sched_class {
1025        const struct sched_class *next;
1026
1027        void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
1028        void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
1029        void (*yield_task) (struct rq *rq);
1030
1031        void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int sync);
1032
1033        struct task_struct * (*pick_next_task) (struct rq *rq);
1034        void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1035
1036#ifdef CONFIG_SMP
1037        int  (*select_task_rq)(struct task_struct *p, int sync);
1038
1039        unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
1040                        struct rq *busiest, unsigned long max_load_move,
1041                        struct sched_domain *sd, enum cpu_idle_type idle,
1042                        int *all_pinned, int *this_best_prio);
1043
1044        int (*move_one_task) (struct rq *this_rq, int this_cpu,
1045                              struct rq *busiest, struct sched_domain *sd,
1046                              enum cpu_idle_type idle);
1047        void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1048        int (*needs_post_schedule) (struct rq *this_rq);
1049        void (*post_schedule) (struct rq *this_rq);
1050        void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
1051
1052        void (*set_cpus_allowed)(struct task_struct *p,
1053                                 const struct cpumask *newmask);
1054
1055        void (*rq_online)(struct rq *rq);
1056        void (*rq_offline)(struct rq *rq);
1057#endif
1058
1059        void (*set_curr_task) (struct rq *rq);
1060        void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1061        void (*task_new) (struct rq *rq, struct task_struct *p);
1062
1063        void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1064                               int running);
1065        void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1066                             int running);
1067        void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1068                             int oldprio, int running);
1069
1070#ifdef CONFIG_FAIR_GROUP_SCHED
1071        void (*moved_group) (struct task_struct *p);
1072#endif
1073};
1074
1075struct load_weight {
1076        unsigned long weight, inv_weight;
1077};
1078
1079/*
1080 * CFS stats for a schedulable entity (task, task-group etc)
1081 *
1082 * Current field usage histogram:
1083 *
1084 *     4 se->block_start
1085 *     4 se->run_node
1086 *     4 se->sleep_start
1087 *     6 se->load.weight
1088 */
1089struct sched_entity {
1090        struct load_weight      load;           /* for load-balancing */
1091        struct rb_node          run_node;
1092        struct list_head        group_node;
1093        unsigned int            on_rq;
1094
1095        u64                     exec_start;
1096        u64                     sum_exec_runtime;
1097        u64                     vruntime;
1098        u64                     prev_sum_exec_runtime;
1099
1100        u64                     last_wakeup;
1101        u64                     avg_overlap;
1102
1103        u64                     nr_migrations;
1104
1105        u64                     start_runtime;
1106        u64                     avg_wakeup;
1107
1108#ifdef CONFIG_SCHEDSTATS
1109        u64                     wait_start;
1110        u64                     wait_max;
1111        u64                     wait_count;
1112        u64                     wait_sum;
1113
1114        u64                     sleep_start;
1115        u64                     sleep_max;
1116        s64                     sum_sleep_runtime;
1117
1118        u64                     block_start;
1119        u64                     block_max;
1120        u64                     exec_max;
1121        u64                     slice_max;
1122
1123        u64                     nr_migrations_cold;
1124        u64                     nr_failed_migrations_affine;
1125        u64                     nr_failed_migrations_running;
1126        u64                     nr_failed_migrations_hot;
1127        u64                     nr_forced_migrations;
1128        u64                     nr_forced2_migrations;
1129
1130        u64                     nr_wakeups;
1131        u64                     nr_wakeups_sync;
1132        u64                     nr_wakeups_migrate;
1133        u64                     nr_wakeups_local;
1134        u64                     nr_wakeups_remote;
1135        u64                     nr_wakeups_affine;
1136        u64                     nr_wakeups_affine_attempts;
1137        u64                     nr_wakeups_passive;
1138        u64                     nr_wakeups_idle;
1139#endif
1140
1141#ifdef CONFIG_FAIR_GROUP_SCHED
1142        struct sched_entity     *parent;
1143        /* rq on which this entity is (to be) queued: */
1144        struct cfs_rq           *cfs_rq;
1145        /* rq "owned" by this entity/group: */
1146        struct cfs_rq           *my_q;
1147#endif
1148};
1149
1150struct sched_rt_entity {
1151        struct list_head run_list;
1152        unsigned long timeout;
1153        unsigned int time_slice;
1154        int nr_cpus_allowed;
1155
1156        struct sched_rt_entity *back;
1157#ifdef CONFIG_RT_GROUP_SCHED
1158        struct sched_rt_entity  *parent;
1159        /* rq on which this entity is (to be) queued: */
1160        struct rt_rq            *rt_rq;
1161        /* rq "owned" by this entity/group: */
1162        struct rt_rq            *my_q;
1163#endif
1164};
1165
1166struct task_struct {
1167        volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1168        void *stack;
1169        atomic_t usage;
1170        unsigned int flags;     /* per process flags, defined below */
1171        unsigned int ptrace;
1172
1173        int lock_depth;         /* BKL lock depth */
1174
1175#ifdef CONFIG_SMP
1176#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1177        int oncpu;
1178#endif
1179#endif
1180
1181        int prio, static_prio, normal_prio;
1182        unsigned int rt_priority;
1183        const struct sched_class *sched_class;
1184        struct sched_entity se;
1185        struct sched_rt_entity rt;
1186
1187#ifdef CONFIG_PREEMPT_NOTIFIERS
1188        /* list of struct preempt_notifier: */
1189        struct hlist_head preempt_notifiers;
1190#endif
1191
1192        /*
1193         * fpu_counter contains the number of consecutive context switches
1194         * that the FPU is used. If this is over a threshold, the lazy fpu
1195         * saving becomes unlazy to save the trap. This is an unsigned char
1196         * so that after 256 times the counter wraps and the behavior turns
1197         * lazy again; this to deal with bursty apps that only use FPU for
1198         * a short time
1199         */
1200        unsigned char fpu_counter;
1201        s8 oomkilladj; /* OOM kill score adjustment (bit shift). */
1202#ifdef CONFIG_BLK_DEV_IO_TRACE
1203        unsigned int btrace_seq;
1204#endif
1205
1206        unsigned int policy;
1207        cpumask_t cpus_allowed;
1208
1209#ifdef CONFIG_PREEMPT_RCU
1210        int rcu_read_lock_nesting;
1211        int rcu_flipctr_idx;
1212#endif /* #ifdef CONFIG_PREEMPT_RCU */
1213
1214#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1215        struct sched_info sched_info;
1216#endif
1217
1218        struct list_head tasks;
1219        struct plist_node pushable_tasks;
1220
1221        struct mm_struct *mm, *active_mm;
1222
1223/* task state */
1224        struct linux_binfmt *binfmt;
1225        int exit_state;
1226        int exit_code, exit_signal;
1227        int pdeath_signal;  /*  The signal sent when the parent dies  */
1228        /* ??? */
1229        unsigned int personality;
1230        unsigned did_exec:1;
1231        unsigned in_execve:1;   /* Tell the LSMs that the process is doing an
1232                                 * execve */
1233        pid_t pid;
1234        pid_t tgid;
1235
1236        /* Canary value for the -fstack-protector gcc feature */
1237        unsigned long stack_canary;
1238
1239        /* 
1240         * pointers to (original) parent process, youngest child, younger sibling,
1241         * older sibling, respectively.  (p->father can be replaced with 
1242         * p->real_parent->pid)
1243         */
1244        struct task_struct *real_parent; /* real parent process */
1245        struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1246        /*
1247         * children/sibling forms the list of my natural children
1248         */
1249        struct list_head children;      /* list of my children */
1250        struct list_head sibling;       /* linkage in my parent's children list */
1251        struct task_struct *group_leader;       /* threadgroup leader */
1252
1253        /*
1254         * ptraced is the list of tasks this task is using ptrace on.
1255         * This includes both natural children and PTRACE_ATTACH targets.
1256         * p->ptrace_entry is p's link on the p->parent->ptraced list.
1257         */
1258        struct list_head ptraced;
1259        struct list_head ptrace_entry;
1260
1261        /*
1262         * This is the tracer handle for the ptrace BTS extension.
1263         * This field actually belongs to the ptracer task.
1264         */
1265        struct bts_context *bts;
1266
1267        /* PID/PID hash table linkage. */
1268        struct pid_link pids[PIDTYPE_MAX];
1269        struct list_head thread_group;
1270
1271        struct completion *vfork_done;          /* for vfork() */
1272        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1273        int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1274
1275        cputime_t utime, stime, utimescaled, stimescaled;
1276        cputime_t gtime;
1277        cputime_t prev_utime, prev_stime;
1278        unsigned long nvcsw, nivcsw; /* context switch counts */
1279        struct timespec start_time;             /* monotonic time */
1280        struct timespec real_start_time;        /* boot based time */
1281/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1282        unsigned long min_flt, maj_flt;
1283
1284        struct task_cputime cputime_expires;
1285        struct list_head cpu_timers[3];
1286
1287/* process credentials */
1288        const struct cred *real_cred;   /* objective and real subjective task
1289                                         * credentials (COW) */
1290        const struct cred *cred;        /* effective (overridable) subjective task
1291                                         * credentials (COW) */
1292        struct mutex cred_guard_mutex;  /* guard against foreign influences on
1293                                         * credential calculations
1294                                         * (notably. ptrace) */
1295
1296        char comm[TASK_COMM_LEN]; /* executable name excluding path
1297                                     - access with [gs]et_task_comm (which lock
1298                                       it with task_lock())
1299                                     - initialized normally by flush_old_exec */
1300/* file system info */
1301        int link_count, total_link_count;
1302#ifdef CONFIG_SYSVIPC
1303/* ipc stuff */
1304        struct sysv_sem sysvsem;
1305#endif
1306#ifdef CONFIG_DETECT_HUNG_TASK
1307/* hung task detection */
1308        unsigned long last_switch_count;
1309#endif
1310/* CPU-specific state of this task */
1311        struct thread_struct thread;
1312/* filesystem information */
1313        struct fs_struct *fs;
1314/* open file information */
1315        struct files_struct *files;
1316/* namespaces */
1317        struct nsproxy *nsproxy;
1318/* signal handlers */
1319        struct signal_struct *signal;
1320        struct sighand_struct *sighand;
1321
1322        sigset_t blocked, real_blocked;
1323        sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1324        struct sigpending pending;
1325
1326        unsigned long sas_ss_sp;
1327        size_t sas_ss_size;
1328        int (*notifier)(void *priv);
1329        void *notifier_data;
1330        sigset_t *notifier_mask;
1331        struct audit_context *audit_context;
1332#ifdef CONFIG_AUDITSYSCALL
1333        uid_t loginuid;
1334        unsigned int sessionid;
1335#endif
1336        seccomp_t seccomp;
1337
1338/* Thread group tracking */
1339        u32 parent_exec_id;
1340        u32 self_exec_id;
1341/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1342 * mempolicy */
1343        spinlock_t alloc_lock;
1344
1345#ifdef CONFIG_GENERIC_HARDIRQS
1346        /* IRQ handler threads */
1347        struct irqaction *irqaction;
1348#endif
1349
1350        /* Protection of the PI data structures: */
1351        spinlock_t pi_lock;
1352
1353#ifdef CONFIG_RT_MUTEXES
1354        /* PI waiters blocked on a rt_mutex held by this task */
1355        struct plist_head pi_waiters;
1356        /* Deadlock detection and priority inheritance handling */
1357        struct rt_mutex_waiter *pi_blocked_on;
1358#endif
1359
1360#ifdef CONFIG_DEBUG_MUTEXES
1361        /* mutex deadlock detection */
1362        struct mutex_waiter *blocked_on;
1363#endif
1364#ifdef CONFIG_TRACE_IRQFLAGS
1365        unsigned int irq_events;
1366        int hardirqs_enabled;
1367        unsigned long hardirq_enable_ip;
1368        unsigned int hardirq_enable_event;
1369        unsigned long hardirq_disable_ip;
1370        unsigned int hardirq_disable_event;
1371        int softirqs_enabled;
1372        unsigned long softirq_disable_ip;
1373        unsigned int softirq_disable_event;
1374        unsigned long softirq_enable_ip;
1375        unsigned int softirq_enable_event;
1376        int hardirq_context;
1377        int softirq_context;
1378#endif
1379#ifdef CONFIG_LOCKDEP
1380# define MAX_LOCK_DEPTH 48UL
1381        u64 curr_chain_key;
1382        int lockdep_depth;
1383        unsigned int lockdep_recursion;
1384        struct held_lock held_locks[MAX_LOCK_DEPTH];
1385        gfp_t lockdep_reclaim_gfp;
1386#endif
1387
1388/* journalling filesystem info */
1389        void *journal_info;
1390
1391/* stacked block device info */
1392        struct bio *bio_list, **bio_tail;
1393
1394/* VM state */
1395        struct reclaim_state *reclaim_state;
1396
1397        struct backing_dev_info *backing_dev_info;
1398
1399        struct io_context *io_context;
1400
1401        unsigned long ptrace_message;
1402        siginfo_t *last_siginfo; /* For ptrace use.  */
1403        struct task_io_accounting ioac;
1404#if defined(CONFIG_TASK_XACCT)
1405        u64 acct_rss_mem1;      /* accumulated rss usage */
1406        u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1407        cputime_t acct_timexpd; /* stime + utime since last update */
1408#endif
1409#ifdef CONFIG_CPUSETS
1410        nodemask_t mems_allowed;        /* Protected by alloc_lock */
1411        int cpuset_mem_spread_rotor;
1412#endif
1413#ifdef CONFIG_CGROUPS
1414        /* Control Group info protected by css_set_lock */
1415        struct css_set *cgroups;
1416        /* cg_list protected by css_set_lock and tsk->alloc_lock */
1417        struct list_head cg_list;
1418#endif
1419#ifdef CONFIG_FUTEX
1420        struct robust_list_head __user *robust_list;
1421#ifdef CONFIG_COMPAT
1422        struct compat_robust_list_head __user *compat_robust_list;
1423#endif
1424        struct list_head pi_state_list;
1425        struct futex_pi_state *pi_state_cache;
1426#endif
1427#ifdef CONFIG_PERF_COUNTERS
1428        struct perf_counter_context *perf_counter_ctxp;
1429        struct mutex perf_counter_mutex;
1430        struct list_head perf_counter_list;
1431#endif
1432#ifdef CONFIG_NUMA
1433        struct mempolicy *mempolicy;    /* Protected by alloc_lock */
1434        short il_next;
1435#endif
1436        atomic_t fs_excl;       /* holding fs exclusive resources */
1437        struct rcu_head rcu;
1438
1439        /*
1440         * cache last used pipe for splice
1441         */
1442        struct pipe_inode_info *splice_pipe;
1443#ifdef  CONFIG_TASK_DELAY_ACCT
1444        struct task_delay_info *delays;
1445#endif
1446#ifdef CONFIG_FAULT_INJECTION
1447        int make_it_fail;
1448#endif
1449        struct prop_local_single dirties;
1450#ifdef CONFIG_LATENCYTOP
1451        int latency_record_count;
1452        struct latency_record latency_record[LT_SAVECOUNT];
1453#endif
1454        /*
1455         * time slack values; these are used to round up poll() and
1456         * select() etc timeout values. These are in nanoseconds.
1457         */
1458        unsigned long timer_slack_ns;
1459        unsigned long default_timer_slack_ns;
1460
1461        struct list_head        *scm_work_list;
1462#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1463        /* Index of current stored adress in ret_stack */
1464        int curr_ret_stack;
1465        /* Stack of return addresses for return function tracing */
1466        struct ftrace_ret_stack *ret_stack;
1467        /* time stamp for last schedule */
1468        unsigned long long ftrace_timestamp;
1469        /*
1470         * Number of functions that haven't been traced
1471         * because of depth overrun.
1472         */
1473        atomic_t trace_overrun;
1474        /* Pause for the tracing */
1475        atomic_t tracing_graph_pause;
1476#endif
1477#ifdef CONFIG_TRACING
1478        /* state flags for use by tracers */
1479        unsigned long trace;
1480        /* bitmask of trace recursion */
1481        unsigned long trace_recursion;
1482#endif /* CONFIG_TRACING */
1483};
1484
1485/* Future-safe accessor for struct task_struct's cpus_allowed. */
1486#define tsk_cpumask(tsk) (&(tsk)->cpus_allowed)
1487
1488/*
1489 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1490 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1491 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1492 * values are inverted: lower p->prio value means higher priority.
1493 *
1494 * The MAX_USER_RT_PRIO value allows the actual maximum
1495 * RT priority to be separate from the value exported to
1496 * user-space.  This allows kernel threads to set their
1497 * priority to a value higher than any user task. Note:
1498 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1499 */
1500
1501#define MAX_USER_RT_PRIO        100
1502#define MAX_RT_PRIO             MAX_USER_RT_PRIO
1503
1504#define MAX_PRIO                (MAX_RT_PRIO + 40)
1505#define DEFAULT_PRIO            (MAX_RT_PRIO + 20)
1506
1507static inline int rt_prio(int prio)
1508{
1509        if (unlikely(prio < MAX_RT_PRIO))
1510                return 1;
1511        return 0;
1512}
1513
1514static inline int rt_task(struct task_struct *p)
1515{
1516        return rt_prio(p->prio);
1517}
1518
1519static inline struct pid *task_pid(struct task_struct *task)
1520{
1521        return task->pids[PIDTYPE_PID].pid;
1522}
1523
1524static inline struct pid *task_tgid(struct task_struct *task)
1525{
1526        return task->group_leader->pids[PIDTYPE_PID].pid;
1527}
1528
1529/*
1530 * Without tasklist or rcu lock it is not safe to dereference
1531 * the result of task_pgrp/task_session even if task == current,
1532 * we can race with another thread doing sys_setsid/sys_setpgid.
1533 */
1534static inline struct pid *task_pgrp(struct task_struct *task)
1535{
1536        return task->group_leader->pids[PIDTYPE_PGID].pid;
1537}
1538
1539static inline struct pid *task_session(struct task_struct *task)
1540{
1541        return task->group_leader->pids[PIDTYPE_SID].pid;
1542}
1543
1544struct pid_namespace;
1545
1546/*
1547 * the helpers to get the task's different pids as they are seen
1548 * from various namespaces
1549 *
1550 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1551 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1552 *                     current.
1553 * task_xid_nr_ns()  : id seen from the ns specified;
1554 *
1555 * set_task_vxid()   : assigns a virtual id to a task;
1556 *
1557 * see also pid_nr() etc in include/linux/pid.h
1558 */
1559pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1560                        struct pid_namespace *ns);
1561
1562static inline pid_t task_pid_nr(struct task_struct *tsk)
1563{
1564        return tsk->pid;
1565}
1566
1567static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1568                                        struct pid_namespace *ns)
1569{
1570        return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1571}
1572
1573static inline pid_t task_pid_vnr(struct task_struct *tsk)
1574{
1575        return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1576}
1577
1578
1579static inline pid_t task_tgid_nr(struct task_struct *tsk)
1580{
1581        return tsk->tgid;
1582}
1583
1584pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1585
1586static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1587{
1588        return pid_vnr(task_tgid(tsk));
1589}
1590
1591
1592static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1593                                        struct pid_namespace *ns)
1594{
1595        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1596}
1597
1598static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1599{
1600        return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1601}
1602
1603
1604static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1605                                        struct pid_namespace *ns)
1606{
1607        return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1608}
1609
1610static inline pid_t task_session_vnr(struct task_struct *tsk)
1611{
1612        return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1613}
1614
1615/* obsolete, do not use */
1616static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1617{
1618        return task_pgrp_nr_ns(tsk, &init_pid_ns);
1619}
1620
1621/**
1622 * pid_alive - check that a task structure is not stale
1623 * @p: Task structure to be checked.
1624 *
1625 * Test if a process is not yet dead (at most zombie state)
1626 * If pid_alive fails, then pointers within the task structure
1627 * can be stale and must not be dereferenced.
1628 */
1629static inline int pid_alive(struct task_struct *p)
1630{
1631        return p->pids[PIDTYPE_PID].pid != NULL;
1632}
1633
1634/**
1635 * is_global_init - check if a task structure is init
1636 * @tsk: Task structure to be checked.
1637 *
1638 * Check if a task structure is the first user space task the kernel created.
1639 */
1640static inline int is_global_init(struct task_struct *tsk)
1641{
1642        return tsk->pid == 1;
1643}
1644
1645/*
1646 * is_container_init:
1647 * check whether in the task is init in its own pid namespace.
1648 */
1649extern int is_container_init(struct task_struct *tsk);
1650
1651extern struct pid *cad_pid;
1652
1653extern void free_task(struct task_struct *tsk);
1654#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1655
1656extern void __put_task_struct(struct task_struct *t);
1657
1658static inline void put_task_struct(struct task_struct *t)
1659{
1660        if (atomic_dec_and_test(&t->usage))
1661                __put_task_struct(t);
1662}
1663
1664extern cputime_t task_utime(struct task_struct *p);
1665extern cputime_t task_stime(struct task_struct *p);
1666extern cputime_t task_gtime(struct task_struct *p);
1667
1668/*
1669 * Per process flags
1670 */
1671#define PF_ALIGNWARN    0x00000001      /* Print alignment warning msgs */
1672                                        /* Not implemented yet, only for 486*/
1673#define PF_STARTING     0x00000002      /* being created */
1674#define PF_EXITING      0x00000004      /* getting shut down */
1675#define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
1676#define PF_VCPU         0x00000010      /* I'm a virtual CPU */
1677#define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
1678#define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
1679#define PF_DUMPCORE     0x00000200      /* dumped core */
1680#define PF_SIGNALED     0x00000400      /* killed by a signal */
1681#define PF_MEMALLOC     0x00000800      /* Allocating memory */
1682#define PF_FLUSHER      0x00001000      /* responsible for disk writeback */
1683#define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
1684#define PF_FREEZING     0x00004000      /* freeze in progress. do not account to load */
1685#define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
1686#define PF_FROZEN       0x00010000      /* frozen for system suspend */
1687#define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
1688#define PF_KSWAPD       0x00040000      /* I am kswapd */
1689#define PF_SWAPOFF      0x00080000      /* I am in swapoff */
1690#define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
1691#define PF_KTHREAD      0x00200000      /* I am a kernel thread */
1692#define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
1693#define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
1694#define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
1695#define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
1696#define PF_THREAD_BOUND 0x04000000      /* Thread bound to specific cpu */
1697#define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
1698#define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
1699#define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezeable */
1700#define PF_FREEZER_NOSIG 0x80000000     /* Freezer won't send signals to it */
1701
1702/*
1703 * Only the _current_ task can read/write to tsk->flags, but other
1704 * tasks can access tsk->flags in readonly mode for example
1705 * with tsk_used_math (like during threaded core dumping).
1706 * There is however an exception to this rule during ptrace
1707 * or during fork: the ptracer task is allowed to write to the
1708 * child->flags of its traced child (same goes for fork, the parent
1709 * can write to the child->flags), because we're guaranteed the
1710 * child is not running and in turn not changing child->flags
1711 * at the same time the parent does it.
1712 */
1713#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1714#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1715#define clear_used_math() clear_stopped_child_used_math(current)
1716#define set_used_math() set_stopped_child_used_math(current)
1717#define conditional_stopped_child_used_math(condition, child) \
1718        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1719#define conditional_used_math(condition) \
1720        conditional_stopped_child_used_math(condition, current)
1721#define copy_to_stopped_child_used_math(child) \
1722        do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1723/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1724#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1725#define used_math() tsk_used_math(current)
1726
1727#ifdef CONFIG_SMP
1728extern int set_cpus_allowed_ptr(struct task_struct *p,
1729                                const struct cpumask *new_mask);
1730#else
1731static inline int set_cpus_allowed_ptr(struct task_struct *p,
1732                                       const struct cpumask *new_mask)
1733{
1734        if (!cpumask_test_cpu(0, new_mask))
1735                return -EINVAL;
1736        return 0;
1737}
1738#endif
1739static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1740{
1741        return set_cpus_allowed_ptr(p, &new_mask);
1742}
1743
1744/*
1745 * Architectures can set this to 1 if they have specified
1746 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1747 * but then during bootup it turns out that sched_clock()
1748 * is reliable after all:
1749 */
1750#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1751extern int sched_clock_stable;
1752#endif
1753
1754extern unsigned long long sched_clock(void);
1755
1756extern void sched_clock_init(void);
1757extern u64 sched_clock_cpu(int cpu);
1758
1759#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1760static inline void sched_clock_tick(void)
1761{
1762}
1763
1764static inline void sched_clock_idle_sleep_event(void)
1765{
1766}
1767
1768static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1769{
1770}
1771#else
1772extern void sched_clock_tick(void);
1773extern void sched_clock_idle_sleep_event(void);
1774extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1775#endif
1776
1777/*
1778 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1779 * clock constructed from sched_clock():
1780 */
1781extern unsigned long long cpu_clock(int cpu);
1782
1783extern unsigned long long
1784task_sched_runtime(struct task_struct *task);
1785extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1786
1787/* sched_exec is called by processes performing an exec */
1788#ifdef CONFIG_SMP
1789extern void sched_exec(void);
1790#else
1791#define sched_exec()   {}
1792#endif
1793
1794extern void sched_clock_idle_sleep_event(void);
1795extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1796
1797#ifdef CONFIG_HOTPLUG_CPU
1798extern void idle_task_exit(void);
1799#else
1800static inline void idle_task_exit(void) {}
1801#endif
1802
1803extern void sched_idle_next(void);
1804
1805#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1806extern void wake_up_idle_cpu(int cpu);
1807#else
1808static inline void wake_up_idle_cpu(int cpu) { }
1809#endif
1810
1811extern unsigned int sysctl_sched_latency;
1812extern unsigned int sysctl_sched_min_granularity;
1813extern unsigned int sysctl_sched_wakeup_granularity;
1814extern unsigned int sysctl_sched_shares_ratelimit;
1815extern unsigned int sysctl_sched_shares_thresh;
1816#ifdef CONFIG_SCHED_DEBUG
1817extern unsigned int sysctl_sched_child_runs_first;
1818extern unsigned int sysctl_sched_features;
1819extern unsigned int sysctl_sched_migration_cost;
1820extern unsigned int sysctl_sched_nr_migrate;
1821extern unsigned int sysctl_timer_migration;
1822
1823int sched_nr_latency_handler(struct ctl_table *table, int write,
1824                struct file *file, void __user *buffer, size_t *length,
1825                loff_t *ppos);
1826#endif
1827#ifdef CONFIG_SCHED_DEBUG
1828static inline unsigned int get_sysctl_timer_migration(void)
1829{
1830        return sysctl_timer_migration;
1831}
1832#else
1833static inline unsigned int get_sysctl_timer_migration(void)
1834{
1835        return 1;
1836}
1837#endif
1838extern unsigned int sysctl_sched_rt_period;
1839extern int sysctl_sched_rt_runtime;
1840
1841int sched_rt_handler(struct ctl_table *table, int write,
1842                struct file *filp, void __user *buffer, size_t *lenp,
1843                loff_t *ppos);
1844
1845extern unsigned int sysctl_sched_compat_yield;
1846
1847#ifdef CONFIG_RT_MUTEXES
1848extern int rt_mutex_getprio(struct task_struct *p);
1849extern void rt_mutex_setprio(struct task_struct *p, int prio);
1850extern void rt_mutex_adjust_pi(struct task_struct *p);
1851#else
1852static inline int rt_mutex_getprio(struct task_struct *p)
1853{
1854        return p->normal_prio;
1855}
1856# define rt_mutex_adjust_pi(p)          do { } while (0)
1857#endif
1858
1859extern void set_user_nice(struct task_struct *p, long nice);
1860extern int task_prio(const struct task_struct *p);
1861extern int task_nice(const struct task_struct *p);
1862extern int can_nice(const struct task_struct *p, const int nice);
1863extern int task_curr(const struct task_struct *p);
1864extern int idle_cpu(int cpu);
1865extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1866extern int sched_setscheduler_nocheck(struct task_struct *, int,
1867                                      struct sched_param *);
1868extern struct task_struct *idle_task(int cpu);
1869extern struct task_struct *curr_task(int cpu);
1870extern void set_curr_task(int cpu, struct task_struct *p);
1871
1872void yield(void);
1873
1874/*
1875 * The default (Linux) execution domain.
1876 */
1877extern struct exec_domain       default_exec_domain;
1878
1879union thread_union {
1880        struct thread_info thread_info;
1881        unsigned long stack[THREAD_SIZE/sizeof(long)];
1882};
1883
1884#ifndef __HAVE_ARCH_KSTACK_END
1885static inline int kstack_end(void *addr)
1886{
1887        /* Reliable end of stack detection:
1888         * Some APM bios versions misalign the stack
1889         */
1890        return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1891}
1892#endif
1893
1894extern union thread_union init_thread_union;
1895extern struct task_struct init_task;
1896
1897extern struct   mm_struct init_mm;
1898
1899extern struct pid_namespace init_pid_ns;
1900
1901/*
1902 * find a task by one of its numerical ids
1903 *
1904 * find_task_by_pid_ns():
1905 *      finds a task by its pid in the specified namespace
1906 * find_task_by_vpid():
1907 *      finds a task by its virtual pid
1908 *
1909 * see also find_vpid() etc in include/linux/pid.h
1910 */
1911
1912extern struct task_struct *find_task_by_vpid(pid_t nr);
1913extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1914                struct pid_namespace *ns);
1915
1916extern void __set_special_pids(struct pid *pid);
1917
1918/* per-UID process charging. */
1919extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1920static inline struct user_struct *get_uid(struct user_struct *u)
1921{
1922        atomic_inc(&u->__count);
1923        return u;
1924}
1925extern void free_uid(struct user_struct *);
1926extern void release_uids(struct user_namespace *ns);
1927
1928#include <asm/current.h>
1929
1930extern void do_timer(unsigned long ticks);
1931
1932extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1933extern int wake_up_process(struct task_struct *tsk);
1934extern void wake_up_new_task(struct task_struct *tsk,
1935                                unsigned long clone_flags);
1936#ifdef CONFIG_SMP
1937 extern void kick_process(struct task_struct *tsk);
1938#else
1939 static inline void kick_process(struct task_struct *tsk) { }
1940#endif
1941extern void sched_fork(struct task_struct *p, int clone_flags);
1942extern void sched_dead(struct task_struct *p);
1943
1944extern void proc_caches_init(void);
1945extern void flush_signals(struct task_struct *);
1946extern void __flush_signals(struct task_struct *);
1947extern void ignore_signals(struct task_struct *);
1948extern void flush_signal_handlers(struct task_struct *, int force_default);
1949extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
1950
1951static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
1952{
1953        unsigned long flags;
1954        int ret;
1955
1956        spin_lock_irqsave(&tsk->sighand->siglock, flags);
1957        ret = dequeue_signal(tsk, mask, info);
1958        spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
1959
1960        return ret;
1961}       
1962
1963extern void block_all_signals(int (*notifier)(void *priv), void *priv,
1964                              sigset_t *mask);
1965extern void unblock_all_signals(void);
1966extern void release_task(struct task_struct * p);
1967extern int send_sig_info(int, struct siginfo *, struct task_struct *);
1968extern int force_sigsegv(int, struct task_struct *);
1969extern int force_sig_info(int, struct siginfo *, struct task_struct *);
1970extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
1971extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
1972extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
1973extern int kill_pgrp(struct pid *pid, int sig, int priv);
1974extern int kill_pid(struct pid *pid, int sig, int priv);
1975extern int kill_proc_info(int, struct siginfo *, pid_t);
1976extern int do_notify_parent(struct task_struct *, int);
1977extern void force_sig(int, struct task_struct *);
1978extern void force_sig_specific(int, struct task_struct *);
1979extern int send_sig(int, struct task_struct *, int);
1980extern void zap_other_threads(struct task_struct *p);
1981extern struct sigqueue *sigqueue_alloc(void);
1982extern void sigqueue_free(struct sigqueue *);
1983extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
1984extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
1985extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
1986
1987static inline int kill_cad_pid(int sig, int priv)
1988{
1989        return kill_pid(cad_pid, sig, priv);
1990}
1991
1992/* These can be the second arg to send_sig_info/send_group_sig_info.  */
1993#define SEND_SIG_NOINFO ((struct siginfo *) 0)
1994#define SEND_SIG_PRIV   ((struct siginfo *) 1)
1995#define SEND_SIG_FORCED ((struct siginfo *) 2)
1996
1997static inline int is_si_special(const struct siginfo *info)
1998{
1999        return info <= SEND_SIG_FORCED;
2000}
2001
2002/* True if we are on the alternate signal stack.  */
2003
2004static inline int on_sig_stack(unsigned long sp)
2005{
2006        return (sp - current->sas_ss_sp < current->sas_ss_size);
2007}
2008
2009static inline int sas_ss_flags(unsigned long sp)
2010{
2011        return (current->sas_ss_size == 0 ? SS_DISABLE
2012                : on_sig_stack(sp) ? SS_ONSTACK : 0);
2013}
2014
2015/*
2016 * Routines for handling mm_structs
2017 */
2018extern struct mm_struct * mm_alloc(void);
2019
2020/* mmdrop drops the mm and the page tables */
2021extern void __mmdrop(struct mm_struct *);
2022static inline void mmdrop(struct mm_struct * mm)
2023{
2024        if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2025                __mmdrop(mm);
2026}
2027
2028/* mmput gets rid of the mappings and all user-space */
2029extern void mmput(struct mm_struct *);
2030/* Grab a reference to a task's mm, if it is not already going away */
2031extern struct mm_struct *get_task_mm(struct task_struct *task);
2032/* Remove the current tasks stale references to the old mm_struct */
2033extern void mm_release(struct task_struct *, struct mm_struct *);
2034/* Allocate a new mm structure and copy contents from tsk->mm */
2035extern struct mm_struct *dup_mm(struct task_struct *tsk);
2036
2037extern int copy_thread(unsigned long, unsigned long, unsigned long,
2038                        struct task_struct *, struct pt_regs *);
2039extern void flush_thread(void);
2040extern void exit_thread(void);
2041
2042extern void exit_files(struct task_struct *);
2043extern void __cleanup_signal(struct signal_struct *);
2044extern void __cleanup_sighand(struct sighand_struct *);
2045
2046extern void exit_itimers(struct signal_struct *);
2047extern void flush_itimer_signals(void);
2048
2049extern NORET_TYPE void do_group_exit(int);
2050
2051extern void daemonize(const char *, ...);
2052extern int allow_signal(int);
2053extern int disallow_signal(int);
2054
2055extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
2056extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2057struct task_struct *fork_idle(int);
2058
2059extern void set_task_comm(struct task_struct *tsk, char *from);
2060extern char *get_task_comm(char *to, struct task_struct *tsk);
2061
2062#ifdef CONFIG_SMP
2063extern void wait_task_context_switch(struct task_struct *p);
2064extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2065#else
2066static inline void wait_task_context_switch(struct task_struct *p) {}
2067static inline unsigned long wait_task_inactive(struct task_struct *p,
2068                                               long match_state)
2069{
2070        return 1;
2071}
2072#endif
2073
2074#define next_task(p) \
2075        list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2076
2077#define for_each_process(p) \
2078        for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2079
2080extern bool is_single_threaded(struct task_struct *);
2081
2082/*
2083 * Careful: do_each_thread/while_each_thread is a double loop so
2084 *          'break' will not work as expected - use goto instead.
2085 */
2086#define do_each_thread(g, t) \
2087        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2088
2089#define while_each_thread(g, t) \
2090        while ((t = next_thread(t)) != g)
2091
2092/* de_thread depends on thread_group_leader not being a pid based check */
2093#define thread_group_leader(p)  (p == p->group_leader)
2094
2095/* Do to the insanities of de_thread it is possible for a process
2096 * to have the pid of the thread group leader without actually being
2097 * the thread group leader.  For iteration through the pids in proc
2098 * all we care about is that we have a task with the appropriate
2099 * pid, we don't actually care if we have the right task.
2100 */
2101static inline int has_group_leader_pid(struct task_struct *p)
2102{
2103        return p->pid == p->tgid;
2104}
2105
2106static inline
2107int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2108{
2109        return p1->tgid == p2->tgid;
2110}
2111
2112static inline struct task_struct *next_thread(const struct task_struct *p)
2113{
2114        return list_entry_rcu(p->thread_group.next,
2115                              struct task_struct, thread_group);
2116}
2117
2118static inline int thread_group_empty(struct task_struct *p)
2119{
2120        return list_empty(&p->thread_group);
2121}
2122
2123#define delay_group_leader(p) \
2124                (thread_group_leader(p) && !thread_group_empty(p))
2125
2126static inline int task_detached(struct task_struct *p)
2127{
2128        return p->exit_signal == -1;
2129}
2130
2131/*
2132 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2133 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2134 * pins the final release of task.io_context.  Also protects ->cpuset and
2135 * ->cgroup.subsys[].
2136 *
2137 * Nests both inside and outside of read_lock(&tasklist_lock).
2138 * It must not be nested with write_lock_irq(&tasklist_lock),
2139 * neither inside nor outside.
2140 */
2141static inline void task_lock(struct task_struct *p)
2142{
2143        spin_lock(&p->alloc_lock);
2144}
2145
2146static inline void task_unlock(struct task_struct *p)
2147{
2148        spin_unlock(&p->alloc_lock);
2149}
2150
2151extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2152                                                        unsigned long *flags);
2153
2154static inline void unlock_task_sighand(struct task_struct *tsk,
2155                                                unsigned long *flags)
2156{
2157        spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2158}
2159
2160#ifndef __HAVE_THREAD_FUNCTIONS
2161
2162#define task_thread_info(task)  ((struct thread_info *)(task)->stack)
2163#define task_stack_page(task)   ((task)->stack)
2164
2165static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2166{
2167        *task_thread_info(p) = *task_thread_info(org);
2168        task_thread_info(p)->task = p;
2169}
2170
2171static inline unsigned long *end_of_stack(struct task_struct *p)
2172{
2173        return (unsigned long *)(task_thread_info(p) + 1);
2174}
2175
2176#endif
2177
2178static inline int object_is_on_stack(void *obj)
2179{
2180        void *stack = task_stack_page(current);
2181
2182        return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2183}
2184
2185extern void thread_info_cache_init(void);
2186
2187#ifdef CONFIG_DEBUG_STACK_USAGE
2188static inline unsigned long stack_not_used(struct task_struct *p)
2189{
2190        unsigned long *n = end_of_stack(p);
2191
2192        do {    /* Skip over canary */
2193                n++;
2194        } while (!*n);
2195
2196        return (unsigned long)n - (unsigned long)end_of_stack(p);
2197}
2198#endif
2199
2200/* set thread flags in other task's structures
2201 * - see asm/thread_info.h for TIF_xxxx flags available
2202 */
2203static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2204{
2205        set_ti_thread_flag(task_thread_info(tsk), flag);
2206}
2207
2208static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2209{
2210        clear_ti_thread_flag(task_thread_info(tsk), flag);
2211}
2212
2213static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2214{
2215        return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2216}
2217
2218static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2219{
2220        return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2221}
2222
2223static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2224{
2225        return test_ti_thread_flag(task_thread_info(tsk), flag);
2226}
2227
2228static inline void set_tsk_need_resched(struct task_struct *tsk)
2229{
2230        set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2231}
2232
2233static inline void clear_tsk_need_resched(struct task_struct *tsk)
2234{
2235        clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2236}
2237
2238static inline int test_tsk_need_resched(struct task_struct *tsk)
2239{
2240        return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2241}
2242
2243static inline int restart_syscall(void)
2244{
2245        set_tsk_thread_flag(current, TIF_SIGPENDING);
2246        return -ERESTARTNOINTR;
2247}
2248
2249static inline int signal_pending(struct task_struct *p)
2250{
2251        return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2252}
2253
2254extern int __fatal_signal_pending(struct task_struct *p);
2255
2256static inline int fatal_signal_pending(struct task_struct *p)
2257{
2258        return signal_pending(p) && __fatal_signal_pending(p);
2259}
2260
2261static inline int signal_pending_state(long state, struct task_struct *p)
2262{
2263        if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2264                return 0;
2265        if (!signal_pending(p))
2266                return 0;
2267
2268        return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2269}
2270
2271static inline int need_resched(void)
2272{
2273        return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2274}
2275
2276/*
2277 * cond_resched() and cond_resched_lock(): latency reduction via
2278 * explicit rescheduling in places that are safe. The return
2279 * value indicates whether a reschedule was done in fact.
2280 * cond_resched_lock() will drop the spinlock before scheduling,
2281 * cond_resched_softirq() will enable bhs before scheduling.
2282 */
2283extern int _cond_resched(void);
2284#ifdef CONFIG_PREEMPT_BKL
2285static inline int cond_resched(void)
2286{
2287        return 0;
2288}
2289#else
2290static inline int cond_resched(void)
2291{
2292        return _cond_resched();
2293}
2294#endif
2295extern int cond_resched_lock(spinlock_t * lock);
2296extern int cond_resched_softirq(void);
2297static inline int cond_resched_bkl(void)
2298{
2299        return _cond_resched();
2300}
2301
2302/*
2303 * Does a critical section need to be broken due to another
2304 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2305 * but a general need for low latency)
2306 */
2307static inline int spin_needbreak(spinlock_t *lock)
2308{
2309#ifdef CONFIG_PREEMPT
2310        return spin_is_contended(lock);
2311#else
2312        return 0;
2313#endif
2314}
2315
2316/*
2317 * Thread group CPU time accounting.
2318 */
2319void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2320void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2321
2322static inline void thread_group_cputime_init(struct signal_struct *sig)
2323{
2324        sig->cputimer.cputime = INIT_CPUTIME;
2325        spin_lock_init(&sig->cputimer.lock);
2326        sig->cputimer.running = 0;
2327}
2328
2329static inline void thread_group_cputime_free(struct signal_struct *sig)
2330{
2331}
2332
2333/*
2334 * Reevaluate whether the task has signals pending delivery.
2335 * Wake the task if so.
2336 * This is required every time the blocked sigset_t changes.
2337 * callers must hold sighand->siglock.
2338 */
2339extern void recalc_sigpending_and_wake(struct task_struct *t);
2340extern void recalc_sigpending(void);
2341
2342extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2343
2344/*
2345 * Wrappers for p->thread_info->cpu access. No-op on UP.
2346 */
2347#ifdef CONFIG_SMP
2348
2349static inline unsigned int task_cpu(const struct task_struct *p)
2350{
2351        return task_thread_info(p)->cpu;
2352}
2353
2354extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2355
2356#else
2357
2358static inline unsigned int task_cpu(const struct task_struct *p)
2359{
2360        return 0;
2361}
2362
2363static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2364{
2365}
2366
2367#endif /* CONFIG_SMP */
2368
2369extern void arch_pick_mmap_layout(struct mm_struct *mm);
2370
2371#ifdef CONFIG_TRACING
2372extern void
2373__trace_special(void *__tr, void *__data,
2374                unsigned long arg1, unsigned long arg2, unsigned long arg3);
2375#else
2376static inline void
2377__trace_special(void *__tr, void *__data,
2378                unsigned long arg1, unsigned long arg2, unsigned long arg3)
2379{
2380}
2381#endif
2382
2383extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2384extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2385
2386extern void normalize_rt_tasks(void);
2387
2388#ifdef CONFIG_GROUP_SCHED
2389
2390extern struct task_group init_task_group;
2391#ifdef CONFIG_USER_SCHED
2392extern struct task_group root_task_group;
2393extern void set_tg_uid(struct user_struct *user);
2394#endif
2395
2396extern struct task_group *sched_create_group(struct task_group *parent);
2397extern void sched_destroy_group(struct task_group *tg);
2398extern void sched_move_task(struct task_struct *tsk);
2399#ifdef CONFIG_FAIR_GROUP_SCHED
2400extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2401extern unsigned long sched_group_shares(struct task_group *tg);
2402#endif
2403#ifdef CONFIG_RT_GROUP_SCHED
2404extern int sched_group_set_rt_runtime(struct task_group *tg,
2405                                      long rt_runtime_us);
2406extern long sched_group_rt_runtime(struct task_group *tg);
2407extern int sched_group_set_rt_period(struct task_group *tg,
2408                                      long rt_period_us);
2409extern long sched_group_rt_period(struct task_group *tg);
2410extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2411#endif
2412#endif
2413
2414extern int task_can_switch_user(struct user_struct *up,
2415                                        struct task_struct *tsk);
2416
2417#ifdef CONFIG_TASK_XACCT
2418static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2419{
2420        tsk->ioac.rchar += amt;
2421}
2422
2423static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2424{
2425        tsk->ioac.wchar += amt;
2426}
2427
2428static inline void inc_syscr(struct task_struct *tsk)
2429{
2430        tsk->ioac.syscr++;
2431}
2432
2433static inline void inc_syscw(struct task_struct *tsk)
2434{
2435        tsk->ioac.syscw++;
2436}
2437#else
2438static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2439{
2440}
2441
2442static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2443{
2444}
2445
2446static inline void inc_syscr(struct task_struct *tsk)
2447{
2448}
2449
2450static inline void inc_syscw(struct task_struct *tsk)
2451{
2452}
2453#endif
2454
2455#ifndef TASK_SIZE_OF
2456#define TASK_SIZE_OF(tsk)       TASK_SIZE
2457#endif
2458
2459/*
2460 * Call the function if the target task is executing on a CPU right now:
2461 */
2462extern void task_oncpu_function_call(struct task_struct *p,
2463                                     void (*func) (void *info), void *info);
2464
2465
2466#ifdef CONFIG_MM_OWNER
2467extern void mm_update_next_owner(struct mm_struct *mm);
2468extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2469#else
2470static inline void mm_update_next_owner(struct mm_struct *mm)
2471{
2472}
2473
2474static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2475{
2476}
2477#endif /* CONFIG_MM_OWNER */
2478
2479#define TASK_STATE_TO_CHAR_STR "RSDTtZX"
2480
2481#endif /* __KERNEL__ */
2482
2483#endif
2484
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